Scenes from the BBC’s landmark Frozen Planet series, which viewers believed
were filmed in the Arctic, were shot in a zoo, it emerged last night.

In the latest fakery row to hit the Corporation, footage of a polar bear cub being born was filmed in a man-made den in a German animal park.

But the accompanying voiceover from Sir David Attenborough referred to cubs being born “beneath the snow” and the footage was intercut with scenes of polar bears in the wild.

The truth about the sequence was not disclosed in the programme. Only viewers who visited the Frozen Planet website and stumbled across a video by the producer, Kathryn Jeffs, would have learned that they had been watching bears in captivity.

Today Sir David, 85, refused to comment on the revelation. Asked whether he thought the clip may have misled viewers, he said as he left his house: "I'm in a real rush, I've got to go."

Last night the BBC said the script was “carefully worded” and did not mislead the audience.

But John Whittingdale, chairman of the Commons culture, media and sport committee, told the Daily Mirror: “My view has always been that broadcasters should not seek to give viewers a false impression and it is much better if they are entirely open.

“If this was not filmed in the wild it would have been much better to have made that clear in the commentary. It’s questionable how many people would visit the website and find the video clip which explained the circumstances of the filming.”

The scenes were broadcast on November 23 in episode five of the series, which regularly drew eight million viewers.

A polar bear was filmed walking across the Arctic landscape during a blizzard. The camera then cut to a close-up of a female bear with her newborn cubs.

“On these slopes beneath the snow, new lives are beginning. The cubs are born blind and tiny,” the voiceover said.

“In two more months polar bear families will emerge on the snowy slopes all around the Arctic... but for now they lie protected within their icy cocoons.”

The BBC said the script was not misleading because it was not referring to the specific cubs shown in the footage, but to cubs in general.

A spokesman said: “This particular sequence would be impossible to film in the wild. The way the footage was captured is clearly explained on the programme website.”

The spokesman declined to comment on claims that the sequence used fake snow in the zoo scenes to make them appear more authentic.

It is the second time that a Sir David Attenborough documentary has faked a polar bear birth - a 1997 series used footage shot in a Belgian zoo.

Past BBC scandals include Blue Peter faking the winner of a competition and a trailer for a royal documentary that was edited to make it appear as if the Queen had stormed out of a photoshoot.